[stman]

libusb: retain 1024 input reports and expose native queue loss counters

Bursty input can overflow the small libusb receive queue and silently discard old
reports. Port the locally validated 1024-report limit, received/dropped/peak
counters, mutex-protected hid_get_queue_stats() snapshot and close-time logging.
The existing queue and oldest-report discard policy are preserved. Peak depth is
measured before eviction and can reach 1025. Other backends return unsupported;
existing APIs retain their behavior.

The original hardware validation transferred 22658 reports with zero drops and
matching Python/C counters. New Linux checks compile both native backends and
exercise the actual callback using mocked USB operations: overflow boundary,
FIFO retention, invalid pointers and a 22658-report zero-drop synthetic run.
Address/undefined sanitizers passed with leak detection disabled due to sandbox
tracing restrictions. No hardware was accessed. Native builds used cc because
CMake/Autotools are unavailable. Other platforms need CI.

Companion Python contribution: stman/cython-hidapi branch feat/libusb-queue-stats.

Assisted-by: Codex:GPT-6